THE NATIONAL GEOGRAPHIC MAGAZINE
Photograph from Theodore W. Noyes
STRAIGHT HIGH SECTION OF UNION FALL
This is the highest column of Iguazu's descending waters, and the fall
of which it is a part carries the greatest volume.
two cataracts out of one, each about 1oo
feet high.
At the lip of the precipice, Niagara (in
cluding Goat Island) has a total width
of about 5,300 feet. Victoria (including
Livingstone and Cataract islands) has a
total width of about 5,700 feet. At the
lip of the precipice, Iguazu (including the
abnormally projecting island of San Mar
tin) has a contour width (estimated) of
more than Io,ooo feet, or nearly two
miles.
Niagara is the outlet seaward of the
four western Great Lakes, which consti
tute half of the fresh water of the world.
Almost unaffected by the seasons, the
volume of water passing constantly over
Zambezi next to
banks, especially
the falls in deep, broad
stream is tremendous.
Niagara below Grand
Island is two and a
half miles wide.
In similar relation
to the fall, the Zam
bezi in flood is about
two miles wide.
It
drains a large area,
and whether at low or
high water, is a great
river. For a short
period, when at high
est flood, it may pos
sibly compare in vol
ume even with Ni
agara.
Iguazu carries the
smallest volume of
water of the three
great falls. Its stream
is not as broad as that
of the Zambezi and
neither so deep nor so
broad as that of Ni
agara. It is swollen
tremendously in flood,
but so also is Zambezi.
RAPIDS OF THE THREE
FALLS COMPARED
Niagara descends 52
feet in the last mile
above the falls, flow
ing with immense ve
locity in turbulent,
powerful, irresistible
rapids.
Sections of the
the western and eastern
the former, descend in
the swift rapids of the Devil's and East
ern cataracts shortly before taking the
leap; but the great body of the river
moves smoothly and slowly to the very
edge of the chasm.
Iguazu's upper rapids, narrowed to one
half mile in width just before swerving
in course and spreading out fanlike for
the drop over the precipice in the San
Martin section of the falls, are more tur
bulent and menacing than Zambezi's
placid flow, but far less impressive than
Niagara's raging, white-capped flood.
The chasm into which Niagara drops is
1,250 feet wide immediately at the falls,